b'Chapter hapterHypothermiaHypothermia occurs when the warming mechanisms fail. The body core temperature drops to 35C or less due to progressive or prolonged exposure to the cold. Elderly people who may be quite frail, thin and may have a chronic illness are vulnerable. Continued exposure to cold, wet, windy conditions outdoors or immersion in cold water will increase risk of severe hypothermia. Cold water cools the body about 30 times faster than dry air so in the event of immersion, immediate lowering of the body temperature can be dangerous, leading to rapid hypothermia.How to RecogniseHypothermia is categorised as Mild, Moderate and Severe.Mild Hypothermia (35 to 34C)Intense shivering.Cold sometimes numb skin, slurred speech.Disorientation, clumsiness.Apathy (suppression of emotion, feeling, concern).Moderate Hypothermia (34 to 30C)Heart rate slows. Shivering may stop and confusion develops. Difficulty in coordinating.Conscious responses decrease.Severe Hypothermia (30C or less)Shivering has ceased. Unconsciousness with developing rigidity or stiffness.Fixed and dilated pupils.Major organs fail. Very cold to touch. Often appears to be deceased butmay not be.Cardiac arrest may follow. Brain damage is likely however, generally takes longer tooccur, as the brains oxygen requirements are decreased.Ideally, obtaining a core body temperature would confirm the diagnosis and indicate the severity of hypothermia. However, in the out-of-hospital situation there are problems with obtaining an accurate core temperature therefore the level of consciousness is often the best indicator.What is Shivering?The body conserves heat by constricting the blood vessels near the skin. When constriction of the blood vessels fails to keep the body warm, shivering results.Shivering produces heat through muscle contractions. Skin surfaceConstricted blood vesselHeat and Cold Emergency 137Heat and Cold Emergency 137'